Coal-cutter chain



Oct. 2, 195] s. SHEPHERD-SMITH COAL-CUTTER CHAIN Filed July 14, 1947 l atentecl Oct. 2, 1951 UNITED STATES PATENT OFFICE COAL-CUTTER CHAIN Section 1, Public Law 690, August 8, 1946 Patent expires'November 6, 1961 This invention comprises improvements in or relating to tool-carrying chains for coal-cutters and like apparatus, the chain being of the usual edge-cutting type-that is to say the chain is made of links hinged to run in a groove round the edge of a fiat jib and carries tools, usually termed picks, which when the chain is in place on the jib will be more or less symmetrically disposed about the central plane of the 'jib and will project away from the edge of the jib so that in use they cut a'flat groove into which, as it is cut, the jib can be entered. It is an object of the invention to provide a pick-carrying chain of which the parts are simple, and in which provision is made'for-carryingpioks at a number of diiierent angles and 'for overcoming the effects of wear so that the chain has a long life.

In such coal-cutter chains it is usual to provide pick boxes, which may be forged from steel but are sometimes steel castings, or are built up by welding, and which are furnished with holders for picks, the holders in successive pick boxes being set at different angles so that "the picks :each cut in a line which differs fromthe line of the pick in front of it in the chain and thereby a groove can be out in the coal, or the floor beneath the coal, which is Wider than the jib on which the chain runs. Similar apparatus is employed for the cutting of other minerals as well as coal.

The term coal cutter chain as used herein is intended to include such chains when used for cutting other minerals as well as coal. H

As the chains run they wear against the jib and eventually become too much worn away for further use. The present invention contemplates the manufacture of a reversible chain, which, when worn away by use can be reversed to bring fresh wearing parts into engagement with the jib and so have a fresh lease of life.

The present invention provides a coal cutter chain wherein each of the chain links has an apertured projection at one end and 'a :fork at the other, the fork being constituted by side plate portions which are separated from one another throughout the depth of the link as far as their junction with the projection and being adapted to support between them a separate toolcarrying boss, and wherein tool-carrying bosses are welded to the side plate portions on a number of the links of the chain.

5 Claims. (Cl. 262-33) tions to links in tool-carrying chains, there is an advantage in the'ccmbination of such tool-carrying bosses with the separated side-plate portions according to the present invention because as the lower parts of the bosses iit down well between the side-plate portions they are supported efiectively by widely separated lines of welding on the two side-plate portions andthe picks are brought down closer to the line of welding.

While each link may consist of one piece comprising the apertured projection and the separated or forked side portions, preferably according to the present invention each link of the chain consists of two similar forgings, one comprising one side-plate portion of the link and the other comprising the other side-plate portion, and each of which comprises part of the apertured projection end of the link, these side members being assembled side by side in the chain and (in thoselinks which carry tools) united by welding along one edge to the toolboss.

The preferred construction according to the present'invention also provides means for lateral adjustment of the width of the chain to take up Wear. These and other features of the invention will he more clearly understood from the followingdescr-iption which is given by 'wayof example of specific forms of chain in accordance with the invention.

According to a further feature of the invention a pick-carrying chain of the edge-cutting type above referred to is characterised by the fact that the links, including the side plates thereof but excluding the pick-holding bosses, are substantially symmetrical about a plane containing the axes of the hinge-pins so that on detachment of the bosses the links can be reversed and pick-holding bosses can be welded on to the opposite edges of the side plates from those to which they were welded previously.

As a result, according to the present invention, each link of the chain may consist of twosimilar forgings, steel-castings or welded elements, one for one side of the link and the other for the other side of the link, which can be put together in the chain side by side and each of which (in those links which carry picks) is united in the finished chain by welding along one edge to the pick-boss. The invention comprises the side members per se as well as the complete chain.

Referring now to the accompanying drawings:

Figure 1 shows a side elevation of part of a coal-cutter chain constructed according to the invention.

Figure 2 is a plan of the chain illustrated in Figure 1, with the tool-bosses removed, and their position indicated only in chain-line.

Figure 3 is a cross-section through the line 3-3 in Figure 1.

Figure 4 is a perspective view of one side mem ber of a link as used in the construction of chain shown in Figure 1 Figure 5 shows a modification wherein alternate links only of the coal-cutting chain are tool-carrying links.

In carrying the invention into effect, according to one form and as applied by way of example to a pick-carrying chain for a coal-cutter, the chain consists of a series of links II, Figures 1 to 3, jointed together by riveted hinge pins I2. Each of the links II comprises two side members I3, which may be formed either as forgings or castings, and arranged side by side, one of these side members being shown in Figure 4. Each side member I3 consists of a flat platelike body portion I4 which has an eye I5 at one end to receive a rivet I2 which constitutes a hinge pin. At the other end the body portion I4 is recessed at I6 to accommodate the convex end portion of the eye I5 of the next link. The body portion I4 is integral with a boss I! which projects inwards from one side of the body portion. The boss IT is pierced with a hole I8 and constitutes part of the apertured portionhereinbefore referred to, the aperture I8 serving to receive a liner I9. Within the liner is a bushing 39.

On the outside face of each side member I3 there are two flanges 20 and 2I one extending along the upper edge and the other along the lower edge of the side member between the hinge pins constituted by the rivets I2. The flanges 20 and 2| are formed of such dimensions that they can run in one side of the usual T-slotted jib which is provided on a coal cutter. The middle of the flat body portion I4 between the flanges 20 and I2 is pierced so as to provide a dirt-extrusion aperture 22 hereinafter more fully referred to. The inner face of the body portion H1 in the vicinit of the eye I5 is machined to provide a shallow slot 23 which extends longitudinally on each side member I3, this slot cutting across the eye diametrically as shown in Figure 4. The purpose of the slot 23 is to receive two corresponding projections 24 which project from one end (or if desired from both ends) of the bushing 39 and prevent rotation of the bushing as hereinafter described. The slots 23 might be disposed crosswise instead of longitudinally if desired.

Two side members I3 as just described are assembled together to form one complete link. II. They are assembled so that the two bosses or projections I! embrace a single liner I9. There is then inserted a bushing 39 having one or more keys or projections 24, as already described, which projections are able to enter one or both of the slots 23 milled across the eyes I5 of the adjacent side members of the next link of the chain and by such engagement prevent rotation of the bushing 39 relatively to said next link. The two side members I3 of each link II thus assembled together and containing a liner I9 and bushing 39 are caused to enter between the eyes I5 of the side members I3 of the next link of the chain and the rivet I2 is inserted through the bushing and eyes and riveted over. Thus the chain is built up link by link. The rivets may be made, as shown in Figure 3, shouldered at one end to accommodate a conical washer, thus simplifying the riveting-up process.

It will be observed that the side members I3 of each link are spaced apart from each other by a distance equal to the depth of the two bosses H. To the edges 26 of the links II there is welded a tool-boss 21, Figures 1 and 3. The tool-boss 21 may be either forged or cut from a bar of suitable section or may be cast and in section may be either circular or egg-shaped. The rounded bottom portion of each tool-boss 2T rests upon the edges 26 of the side members I3 of the link to which it is attached and owing to the rounded shape the boss can be tilted over to any desired angle before welding and will fit equally well in any position. Each of the tool-bosses 21 is machined or drifted through with a rectangular pick-carrying aperture 28 which usually extends in a plane at right-angles to the plane in which the rivets I2 of the chain lie.

One or both of the end faces of each toolboss 21 is drilled and tapped to receive a picksecuring set screw 29. After welding the toolbosses 2! to the edges 26 of the side members I3 of the links II the chain is complete.

Conveniently each tool-boss 21 will be welded securely to one of the side-members I3 of its link and merely tacked to the other as this facilitates subsequent removal of the tool-boss for overhaul purposes.

By the employment of a tool-boss of which the bottom is of semi-circular or approximately semi-circular shape the tool-bosses may be readily welded in various positions with respect to one another in order to obtain any desired pick-angles. In addition, the particular shape of the bottom of the tool-bosses provides a constant angle for welding between the bosses and the side members of the link.

It is to be noted that the links II as above described are symmetrical about the plane which contains the axes of the rivets I2. The flanges 2|, Figures 1 and 3, run in the sides of the T-slotted jib of the coal-cutter (which thus constitute guides for the chain). These flanges 2I are liable to wear in the jib on account of the lack of lubrication, the presence of stone dust and so forth. When the flanges 2I have become worn to such an extent as to be unserviceable the chain can be reversed if the pick-bosses 21 are first broken-01f along the lines of welding and any additional metal ground flat, thus permitting the unworn flanges 29 to run in the guides of the jib. The pick-bosses 21 are then re-welded to the links II along the opposite edges to those of the side members I3 which had been previously running in the jib. In general, when the chain is thus reversed it will be found that the liners I9 and bushings 39 are worn. It will be recollected that the bushings 39 are prevented from rotation by the engagement of the projections: 24 with the slot 23 on the inner races. oi each link II. Eachside member It ha a. slo 23. on its inner face and; if each bushing is reversed so that, it engages the slot on the opposite side member of the link, the unworn portion of the bushing will be in tension and the chain will then be brought back intopitch and gain a'fu-rth-er lease of life also in this respect. From this it will be seen that the wear which necessarily takes place at the joints, due to oscillation, is absorbed only by the liner I9 and the bushing 38 and that wear is prevented from taking place between the liner I9 and link member I3. Furthermore the liner I9 can be easily and cheaply replaced by a new one when such wear has taken place.

As only a single liner I9 is used in conjunction with each pair of bosses I1 these liners impart lateral stiffness to the links since the side members I3 of the links in effect are connected together by these liners.

The riveting and. breaking of the riveting of rivets I2 is greatly facilitated by the use of shouldered rivets in conjunction with conical washers 25.

The apertures 22 which are cut in the side members I3 of the links I I and are disposed between the flanges 20 and 2| for the purpose of dirt-extrusion permit the teeth of the sprockets. on which the chain runs, which teeth enter the spaces 30 between the links during running, to force any dirt outwardly through these apertures. Dirt tends to enter the spaces 30 while the chain is cutting but as it can be forced out by the sprocket teeth through the openings 22 it does not accumulate or tend to jam against the undersides of the tool-bosses.

It is not essential that a tool-boss 21 should be secured upon every link II of the chain and in Figure 5 a chain is shown in which idle links 3I alternate with links II carrying tool-bosses 21. The idle links 3| comprise, however, two side members I3 which are similar to those from which the links I I, carrying the tool-bosses 21, are made. Every link therefore of the chain can be forged from a single set of dies and the special intermediate links of the typical present-day chains, which serve only as a connection between successive pick-carrying links, are eliminated.

Furthermore provision is made for lateral adjustment of the width of the chain so that it may be made to fit the sides of the T-slot of the jib even if worn, or to fit any width of slot in jibs already in use. Adjustment to bring about increase in width is efiected by inserting a washer 32 of suitable thickness, as shown in Figure 3, between the bosses I! of each pair of side members I3 and the insertion of such washers can be conveniently effected when the chain is being reversed as above described.

The rivets I2 are conveniently made of large diameter to afford ample strength and are left short at one end as this facilitates both riveting and subsequent removal of the rivets for pur-.

boxes. the chain will engage the sprocket teeth,

in idle links and the sprocket teeth. have to be spaced outacjcordingly. .Itiis' therefore possible with a chain according to the invention to space the sprocket teeth to engage every link and thus to double the number of sprocket teeth and reduce their wear, thereby increasing the life of the chain and ensuring smoother running. The chain will, however, run on an ordinary sprocket just as well as existing chains do.

Instead of constructing the links from f'o-rgings, the links can, if desired, be fabricated from pieces cut from steel channel section, the flanges of which will constitute the flanges for engaging with the T-slots of the jib, and bosses being placed on the opposite face of the channel to that carrying the flanges and welded or attached in any other convenient manner. The bosses in such a case can be cut from circular, elliptical or other suitable section bar steel. For another construction each link II can be formed as one unit either by forging, casting or fabrication.

The bosses H on the side members I3 of the links II may be of elliptical, semi-elliptical or other suitable rounded form instead of circular as above described, and in fact they are shown slightly elliptical in the drawing to allow room for thicker sprocket teeth.

I claim:

1. A coal-cutter chain comprising a series of identical links jointed together by hinge-pins wherein each link comprises identical side plates, spaced apart to carry between them welded-0n tool-carrying bosses, each of the side plates having short flanges along each edge of sufficient length to guide the link in the jib of the coalcutter and to afford shelves for the welding but not long enough to overlie the joint at the hingepins, the links, apart from the bosses, being substantially symmetrical about a plane containing the axes of the hinge-pins, so that, on detachment of the bosses the links can be inverted and toolcarrying bosses welded on to the opposite edges of the side plates from those to which they were welded previously.

2. A tool-carrying chain as claimed in claim 1, wherein the side plates of each link are brought together at one end by reason of being joined to an eye which embraces the centre of a hinge-pin and are separated at the other end and comprise eyes also at that end to embrace the outer ends of the hinge-pin of the next link.

3. A coal-cutter chain according to claim 1,

- each tool-carrying boss being convex on its underside where it rests upon the side plate portions of the links and of sufiiciently small radius to bed down substantially between the side plate portions.

4. A side-member for a link of a tool-carrying chain according to claim 1, comprising a plate-like member having flanges on two opposite edges and having eyes for hinge-pins intermediately disposed between the flanges or guides, the formation of the plate-like member being symmetrical about the plane joining the axes of the hinge-pin eyes so as to permit the links of a chain incorporating these side members to be inverted to prolong the life of the chain.

5. A side-member for a link for a tool-carrying chain, as claimed in claim 4, wherein the eye at one end of the side-member is inset from the plane of the plate-like side member so that when assembled in the chain it can lie inwardly of the 8 eye at the adjacent opposite end of the next link Number Name Dat of the chain. 1 2,046,026 Lee June 30, 1936 STEPHEN SHEPHERD-SMITH. 2,398,107 Morrow Apr. 9, 1946 REFERENCES CITED 5 FOREIGN PATENTS v Number Country Date g ii gfisf g are 93 the 466,512 Great Britain May 31, 1937 492,758 Great Britain Sept. 27, 1938 UNITED STATES PATENTS Number Name Date 1 ,308,843 Davis July 8; 1919 

